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Several studies document a U-shaped relationship between systolic blood pressure (SBP) and death in kidney failure (1, 2) and stage 4 and 5 chronic kidney disease (CKD) (3). Whether patients with early CKD also have increased mortality rates with both low and high SBP is unclear. In a clinical trial of proteinuric diabetic nephropathy, SBP less than 120 mm Hg or diastolic blood pressure (DBP) less than 85 mm Hg were associated with adverse cardiovascular outcomes (4). In other hypertensive populations, low DBP has been associated with increased risk for death (5). Low DBP may exert its ill effects through decreasing diastolic filling of the coronary arteries. However, low DBP may be a marker of the severity of vascular disease or vascular stiffness rather than a modifiable risk factor.